Wire drawing apparatus



2 Sheets-Sheet 1 Filed July 15, 1962 INVENTORS. CLAUS LOU/5 KARL H/LGERSDec. 13, 1966 c. LOUIS ETAL WIRE DRAWING APPARATUS 2 Sheets-Sheet 2Filed July 15', 1962 INVENTORS cmus LOU/5 BY KARL H/L ems Toys 8 ji iiUnited States Patent Ofiice 3,290,916 WIRE DRAWING APPARATUS ClausLouis, Solingeu, and Karl Hilgers, Dusseldorf, Germany, assignors toFriedrich Karl Koch, proprietor of Peltzer & Ehlers K.G., Krefeld,Germany Filed July 13, 1962, Ser. No. 209,658 Claims priority,application Germany, duty 27, 1961, P 27,612 8 Claims. ((31. 72-285) Thepresent invention concerns an installation for deforming wires and thelike, comprising a drawing device in combination with a treatmentmachine such as a press disposed at the end of the wire-transport path.It does in fact concern such an installation wherein the drawing devicein addition to a ram rod has a drawing die with drawing tongs whichexecute a movement relative to this die firmly clamping the wire thereinduring each drawing stroke, and wherein the treatment machine isprovided with a draw-in device. The draw-in device of the treatmentmachine serves to introduce the wire, whose cross-section has beenreduced in the drawing device, into the treatment machine in synchronismwith the stroke of the treatment machine. It is necessary there forethat the introduction of the wire into the treatment machine by thedraw-in device be very accurate. To ensure this accurate operation it isnecessary for the draw in device associated with the treatment machineto be subjected to as little stress as possible. That is to say itshould not be required to supply the very considerable power for pullingthe wire through the drawing die which reduces the wire to a smallerdiameter. Known installations conform only imperfectly to theserequirements and are of a complicated structure.

With regard to the drive of prior arrangements for deforming wires andthe like, these have already been so constructed that the power for thedrawing device has been derived from the treatment machine for furtherprocessing of the wire, or in such manner that both have separatedrives. Since however the drawing operation takes place mainly at aperiod in which the treatment machine has to perform the actualdeforming work, it is necessary in the first-mentioned arrangement tomake the drive of the treatment machine correspondingly stronger. If onthe other hand the drawing device and the treatment machine are eachfurnished with a separate drive, it is necessary to have a complexcontrol device for synchronization of the individual devices. Thus, bymeans of this control device in accordance with the timing of thetreatment machine a clutch between the drive for the drawing device andthe drawing device can be automatically engaged and disengaged. Thisengagement and disengagement of the clutch with each stroke producesconsiderable accelerations and braking actions, which have to beadditionally absorbed by the clutch elements and produce heat. It has aparticularly unfavorable effect in the case of rapid stroke sequences,which are required in modern machines with higher outputs.

It is an object of the invention to provide an arrangement for deformingwires and the like which does not show the disadvantages mentioned aboveof known arrangements.

The present arrangement provides an arrangement in which a synchronizedco-operation of drawing device and treatment machine is not required.The solution of the problem consists in the feature that the drawing dieand drawing tongs are arranged integrally, independently of theirmovement relative to one another, on the frame of the drawing device soas to be longitudinally displaceable in the direction of feed of thewire, thus preferably on a sliding guide the length of which amounts toa mul- 3,290,916 Patented Dec. 13, 1966 tiple of the maximum draw-inlength required per stroke of the treatment machine. The drawing-diemeans and the drawing tongs of the clamping means are displaceablyinterconnected by means of the connecting rods of hydraulic workingcylinders of the fluid-responsive means and the working cylinders are tobe connected to a control or master cylinder, the output of which issomewhat greater than the total output of the working cylinder. Theamount of the excess liquid supply is diverted via an excess pressurevalve into a storage container from which the additional liquid requiredfor each stroke is induced. In accordance with a further feature of theinvention, contacts are arranged in the path of the feed means of thewire-drawing device (substantially comprising the drawing die, thedrawing tongs and working cylinders) which includes the sliding guide;the contacts are actuated by contact levers mounted on the drawingdevice and of which contact levers a stop facing the ramming tongs isadapted to disengage an electric switch coupling for actuating thecontrol cylinder, and a stop facing the draw-in device of the treatmentmachine adapted to engage this coupling.

A further preferred feature of the invention consists in the provisionof a further stop behind the contact stop facing the drawing-in devicein the direction of the drawing-in device, which stop is also to beactuated by the contact lever mounted on the drawing device, and whichis adapted to disengage an electric switch coupling for actuating thedraw-in device; the stops constitute an ad justable stop means on thesupport for the slide for limiting the reciprocating movement.

Furthermore the drawing device is lockable on the frame of the drawingapparatus by a releasable index means and in this position connected bymeans of connecting rods projecting from the working cylinders, to rodsdisposed in extension thereof, arranged so as to be longitudinallydisplaceable in the ram tongs and provided with stops and having such alength that the stops of these rods, after effecting the coupling, areable to move the ram tongs a short distance towards the end of a pistonstroke in the direction of the treatment machine in the same direction.On the return stroke of the piston the ram tongs are drawn back by meansof springs against stops adjustable to a certain distance relative tothe advanced ram tongs. In a further feature of the invention it isproposed that for actuating the control cylinder of the hydraulicworking cyilnder a crosshead slide or the like connected with theconnecting rod thereof is provided and driven in such a manner thatduring a variable-time unit the overall length of stroke of the drawingtongs exceeds the draw-in length of this machine caused by 'the draw-indevice of the treatment machine by an adjustable amount.

The invention will be described further, by way of example, withreference to the accompanying drawing, in which:

FIG. 1 is a schematic elevational view of the overall arrangement of aninstallation for deforming wires and the like in accordance with theinvention; and

FIG. 2 is a diagrammatic, fragmentary sectional view of the drivingarrangement of the drawing device.

As shown in FIG. 1, a wire 2 to be unwound from a pay-out reel 1 firstpasses into a wire-drawing apparatus 3. The wire 2 is reduced in adiameter in the device 3 and then continues via a draw-in device 4,constituting a feed means engageable with the wire upon reduction of itscross-section for intermittently advancing it for further processinginto a treatment machine 5 which may for instance be a cold-forming ormolding press. The draw-in device 4 thus feeds the drawn wire 2 into thetreatment machine 5 to an extent necessary for synchronised treatmentthereby. The drawing device 3 on its support means or frame 6 hasramming tongs 7, or inserting means which will be explained in detailhereinafter, and also the actual drawing mechanism or drawing-die means8 which includes a drawing die 9 and drawing tongs 10 as clamping means.The drawing die 9 carries on its sides working cylinders 11 withdouble-acting pistons 12 and piston rods 13 or 14 together forming afluid-responsive means for displacing the clamping means relatively tothe drawing die. The piston rods 13 are thus rigidly connected to thedrawing tongs 10. The piston rids 14 support coupling ends 14a.

The pistons 12 and working cylinders 11 are actuated by means of acontrol means including a master cylinder 15 (see FIG. 2), which in turnis connected to a mechanism for controlling the pistons of the mastercylinder and including driving motor 17 via a transmission gearing 16.During this actuation of the pistons 12 of the working or powercylinders -11, the drawing die 9 and the drawing tongs 10 with onestroke move towards one another and away from one another with thesecond stroke. During the movement of the drawing tongs 10 and of thedrawing die 9 away from one another, clamping jaws 18 arranged on thedrawing tongs 10 are closed, so that the wire 2 is firmly clamped. Thiscauses the die 9 to be drawn over the wire 2. When the drawing tongs 10and drawing die 9 move towards one another, the clamping jaws howeverare open, thus preventing a displacement of the wire 2 relative to thedrawing die 9.

A sliding runner 19 of the drawing device 8 can also be seen on eachside of the working cylinders 11. These sliding runners 19 are adaptedto slide on a .guide 20 which is rigidly mounted on the frame 6. Thelength of the guide 20 should preferably amount to arnultiple of thewire draw-in length of the treatment machine 5 required per stroke. Asthe drawing die 9 and the drawing tongs 10 are interconnected by meansof the piston rods 13, it is possible for the drawing die 9 and thedrawing tongs 10 to be displaced as a whole on the guide 6 independentlyof the movement between drawing tongs 10 and drawing die 9 relative toone another caused by the action of the piston -12. The drawing device 8also has a contact lever 21 mounted thereon which is adapted to actuateseveral contacts 22, 23, 24 mounted in the path of the drawing device 8reciprocated on the .guide 20 and spaced along the guide path whileconnected in circuit with the fluid-responsive means. Thus, contact ofthe contact lever 21 with the contact stop 22 causes a switching clutchsituated in the transmission gearing 16 to be disengaged. This causesthe power transmission from the driving motor 17 of the drawing device 8to the pistons 12 of the working cylinders 11 to be interrupted. Thedrawing device is thus stopped. When the operating lever 21 makescontact with the switch contact 23, the switching clutch 25 is engagedand the drawing device actuated. When the operating lever 21 makescontact with the switch contact 24, the feed device 4 of the treatmentmachine 5 is put out of action by means of a clutch (not shown).

The displaceable arrangement of the drawing device 8 on the slidingguide 20, which constitutes a main feature of the invention, first ofall avoids the need for designing the feed device 4 to performadditional drawing work, when the clamping jaws 18 of the drawing tongs10 do not clamp the wire 2 satisfactorily. If for example, the wholearrangement operates in such a manner that the drawing stroke of thedrawing device 8 coincides with the drawing in of the wire 2 by thedraw-in device 4 into the treatment machine 5, and the clamping jaws 18do not clamp correctly, the drawing device 8 owing to the action of thedraw-in device 4 is only advanced in the direction of the treatmentmachine 5. The effort required for this, in comparison with the effortrequired for drawing the wire 2 through the drawing die 9, isconsiderably lower and can also be performed readily by the draw-indevice 4. The displaceable arrangement of the drawing device 8 has theadvantage compared with known arrangements that it is no longernecessary to synchronize accurately the stroke of the treatment machine5 with the drawing device 8 via a complicated control gearing. It isnecessary only to adjust the draft or stroke of the drawing device 8 insuch a manner that its minimum output corresponds to the wire-lengthincrements required by the treatment machine 5. The drawing stroke ordraft is conveniently so adjusted however that the drawn wire length issomewhat greater than the wire length requirement of the treatmentmachine, and then accurate regulation is not necessary. The differencebetween the draft or stroke of the drawing device 8 occuring with theabove mentioned adjustment and the wire length requirement of thetreatment machine 5 acts so as to cause the drawing device 8 to slideaway slowly from the treatment machine 5 on the sliding guide 20.However, as soon as the contact lever 21 makes contact with the switchcontact 22 the drawing device 8, as already mentioned, is disengaged, sothat no further wire is drawn. The disengaged drawing device 8 is thusadvanced in synchronism with the draw-in device 4. As soon as thecontact lever 21 reaches the switch contact 23 the drawing device is:again engaged and the operation recommenced in that the drawing device8 slides slowly away from the treatment machine 5. In the event of theswitch contact 23 failing to function, so that the drawing device is notengaged, a further switch contact 24 is provided which also, as alreadymentioned, is adapted to be actuated by the contact lever 21, thusputting the draw-in device 4 of the treatment machine 5 out of action.This arrangement is also associated with a warning indication (notshown) for the operator of the installation; it is also associated witha stroke control for the draw-in mechanism, in order to avoid thedraw-in device being disengaged during its advance. Otherwise it wouldbe possible for the length of wire drawing required for the treatmentmachine 5 not to be achieved, which could lead to a breakdown of thetreatment machine 5.

The driving arrangement for the drawing device is shown in more detailin FIG. 2.

The two working cylinders 11 are interconnected by means of the conduits26. One of the two cylinders 11 has displaceable hydraulic conduits 27connected thereto which lead to the control cylinder 15. The controlcylinder 15 has two suction conduits 28 connected thereto, through whichthe liquid necessary for actuating the piston 12 in the workingcylinders 11 is induced from a tank 29. These suction conduits 28 eachhave a nonreturn valve 30 and an excess pressure valve 31. The purposeof the excess pressure Valves 31 is explained below: The displacement ofthe control cylinder 15 in accordance with a feature of the invention isselected to be greater than the capacity of the working cylinder 11.With each stroke of the control cylinder 15 the surplus hydraulic liquidis forced out via the excess pressure valve 31 into the tank 29. Thisensures that the quantity of liquid which is pressurized is sufficientto give a reliable piston movement of the pistons 12 of the workingcylinders 11, thus above all towards the end of the stroke of thepistons 12. The excess-pressure valves 31 are adapted to be adjusted tothe momentarily required liquid pressure, which in any case must behigher than is required in accordance with the drawing force. Acrosshead slide 32 which is guided in a crosshead guide 33 serves theguidance of the connecting rod 34 of the control cylinder 15. Thedriving motor 17 is constructed preferably to be continuously regulable,whereby it is possible, in combination with the transmission gearing 16,to obtain adjustment of the wire-feed increment very sensitively to theinput required by the machine 5. In accordance with a further feature ofthe invention, as

already briefly explained initially, inserting means in the form of ramtongs 7 are also provided on the frame 6 of the drawing device 3. Theram tongs 7 are mounted so as to be longitudinally displaceable in thedirection of the Wire feedv Springs 35 are thus intended to draw the ramtongs in an unloaded state against adjustable stops 36 in the directionof the wire pay-out reel 1. The ram tongs in an unloaded state againstadjustable stops 38 mounted therein so as to be longitudinallydisplaceable in the direction of the wire feed. These rods 37 moreoverform releasable connecting means with coupling halves 39 by means ofwhich they are coupled to the connecting rods 14 of the fluid-responsivemeans 11, 12 etc. For ramming in a wire 2 the drawing device 8 is slidin the direction of the tongs 7 and looked at a rearward location withan index locking device 4% so as to be non-displaceable on the frame 6via an index -11 situated on the frame 6. Then the rods 37 and theconnecting rods 14 are interconnected via their couplings 39 and 14a.The ram tongs 7 is then released by means of an actuating toggle (notshown in the drawing) and the wire end to be rammed is advanced to thedrawing die 9. On eliminating the release of the ram tongs 7, thedrawing device 8 is engaged in by means of a separate switch (also notshown), whilst the switch contacts 22 and 23 are switched off. After thedrawing device 8 has been engaged, the pistons 12 and the Workingcylinders 11, due to the drawing device 8 being fixed, carry out thereciprocating movement simultaneously carrying the sliding rods 37 alongtherewith. When these rods 37 are reciprocated, they then abut at theend of the stroke of the pistons 12 With their stops 38 against the ramtongs 7 in the direction of the treatment machine 5 and advance thetongs 7 somewhat in the direction of the treatment machine. Dependingupon the adjustment of the adjustable stop means 36, the tongs 7 arethus engaged over a small or large distance. During the return stroke ofthe piston the tongs 7 are then drawn back by the springs 35 against thestops 36 in the direction of the Wire pay-out reel 1. With the advanceof the ram tongs 7 in the direction of the treatment machine 5 the ramtongs 7 by means of their clamping jaws 42 clamp the wire so firmly thatthe latter is displaced into and through the die 9. To prevent the wire2 from buckling during the ramming operation, a Wire guide 43 is mountedon the frame 6 behind the ram tongs 7, through which guide the wire 2 isadapted to slide. The aforemen tioned ramming operation is repeateduntil the leading end of the drawn wire is inserted between the clampingjaws 18 of the drawing tongs 10. The jaws of these tongs were open untilthen. They are now closed so as to permit the tongs 10 to clamp the wirein position. On the release of the clamping jaws 42 of the ram tongs 7,drawing of the Wire takes place with the drawing device 8 locked, inthat the tongs 1t) advance the wire, thus by the overall length ofstroke of the piston 12. This is repeated a number of times until theleading end of the wire has reached the draw-in device 4. The locatingdevice 40, 41 is released and simultaneously the couplings 14a and 39are released. Furthermore, the electric contact connection 22, 23 ischanged over to the operative condition.

The draw-in device 4 now draws the wire 2 in synohronism with thetreatment machine 5 and hence also the drawing device 8. When reachingthe contact stop 23 the switch coupling 25 is adapted to be engaged,whereby the actual drawing process commences in combination with theoperation of the treatment machine 5, as already explained before.

The displaceable arrangement in accordance with the invention of thedrawing die and drawing tongs as a whole independently of its relativemovement to one another is adapted to be used not only as describedabove in connection with installations comprising a drawing device andconnected at the end a treatment machine executing in timed sequencealternately a working stroke and an idling stroke, but also in suchinstallations in which the treatment machine does not operate in timedse quence but continuously.

We claim:

1. A wire-drawing apparatus for substantially intermittently advancing awire for further processing while reducing its cross-section, saidapparatus comprising:

intermittently operable feed means engageable with said Wire uponreduction of its cross-section for displacing same in a forwarddirection;

support means rearwardly of said feed means forming a substantiallylinear guide path in said direction; drawing-die means movably mountedon said support means for reciprocation along said guide path; clampingmeans mounted upon said drawing-die means and reciprocable relativelythereto in said direction for releasable entrainment of said wirethrough said drawing-die means;

fluid-responsive means on said drawing-die means connected with saidclamping means for reciprocably displacing the latter relatively to saiddrawing-die means; and

drive means connectable with said feed means for advancing said wire insaid direction together with said drawing-die means and said clampingmeans.

2. A wire-drawing apparatus for substantially intermittently advancing awire for further processing while reducing its cross-section, saidapparatus comprising:

intermittently operable feed means engageable with said wire uponreduction of its cross-section for displacing same in a forwarddirection;

support means rearwardly of said feed means forming a substantiallylinear guide path in said direction; drawing-die means movably mountedon said support means for reciprocation along said guide path;

clamping means mounted upon said drawing-die means and reciprocablerelatively thereto in said direction for releasable entrainment of saidwire through said drawing-die means;

fluid-responsive means on said drawing-die means connected with saidclamping means for reciprocably displacing the latter relatively to saiddrawing-die means; and

drive means connectable with said feed means for advancing said wire insaid direction together with said drawing-die means and said clampingmeans, said apparatus further comprising a pair of electrical contactsspaced along said guide path for operation by said drawing-die meansupon displacement thereof by said feed means, and circuit meansoperatively connecting said contacts with said fluidresponsive means forcontrolling the operation of said clamping means in accordance with themovement of said drawing-die means along said guide path.

3. An apparatus as defined in claim 2, further comprising an additionalcontact disposed along said guide path forwardly of the first-mentionedpair of contacts and further circuit means operatively connecting saidadditional contact with said feed means for decoupling same from saiddrive means upon operation of said additional contact by saiddrawing-die means upon displacement thereof along said guide pair.

4. An apparatus as defined in claim 2 wherein said fluid-responsivemeans includes at least one hydraulic power cylinder mounted upon saiddrawing-die means and a double-acting piston reciproca'ble in saidcylinder and connected with said clamping means, said apparatus furthercomprising control means for said fluid-responsive means, said controlmeans including a master cylinder stationarily mounted upon said supportmeans, flexible conduit means interconnecting said master cylinder andsaid power cylinder, a further piston movable in said master cylinderfor supplying fluid to said power cylinder through said flexible conduitmeans, and a mechanism for displacing said further piston.

5. An apparatus as defined in claim 4 wherein said mechanism includes asource of motive power, a transmission adapted to interconnect saidsource with said further piston, and electrically operable clutch meansin said transmission operable by said contacts for selectivelydecoupling said source from said further piston and coupling said sourcetherewith.

6. An apparatus as defined in claim 4, further comprising a reservoirfor hydraulic fluid connected to said master cylinder, said mastercylinder having a stroke such that its displacement is in excess of thatrequired by the stroke of said power cylinder, said master cylinderbeing provided with a pressure-relief valve communicating with saidreservoir for discharging excess fluid into the latter.

7. A wire-apparatus for substantially intermittently advancing a wirefor further processing while reducing its cross-section, said apparatuscomprising:

feed means engageable with said wire upon reduction of its cross-sectionfor displacing same in a forward direction;

support means rearwardly of said feed means forming a substantiallylinear guide path in said direction; drawing-die means movably mountedon said support means for reciprocation along said guide path; clampingmeans mounted upon said drawing-die means and reciprocable relativelythereto in said direction for releasable entrainment of said wirethrough said drawing-die means;

fluid-responsive means on said drawing-die means connected with saidclamping means for reciprocably displacing the latter relatively to saiddrawing-die means; and i drive means connectable with said feed meansfor advancing said wire in said direction together with said drawing-diemeans and said clamping means, said apparatus further comprisingreleasable index means for locking said drawing-die means to saidsupport means at a relatively rearward location, inserting means mountedon said support means adjacent said location for driving said wirethrough said drawing-die means, and connecting means releasably couplingsaid inserting means with said fluidresponsive means for operationthereby. 8. An apparatus as defined in claim 7, further comprisingadjustable stop means for limiting the reciprocable movement of saidinserting means.

References Cited by the Examiner UNITED STATES PATENTS 1,560,705 11/1925Mayer 2055 2,018,211 10/1935 Hogue 29-33.51 2,255,097 9/1941 Berkebil2933.51 2,597,623 5/1952 Dies et a1. 2055 2,633,233 3/1953 Berkebil205-4 3,195,336 7/1965 Lindemann 72-72 CHARLES W. LANHAM, PrimaryExaminer.

RICHARD H. EANES, Examiner.

H. D. HOINKES, Assistant Examiner.

1. A WIRE-DRAWING APPARATUS FOR SUBSTANTIALLY INTERMITTENTLY ADVANCING AWIRE FOR FURTHER PROCESSING WHILE REDUCING ITS CROSS-SECTION, SAIDAPPARATUS COMPRISING: INTERMITTENTLY OPERABLE FEED MEANS ENGAGEABLE WITHSAID WIRE UPON REDUCTION OF ITS CROSS-SECTION FOR DISPLACING SAME IN AFORWARD DIRECTION; SUPPORT MEANS REARWARDLY OF SAID FEED MEANS FORMING ASUBSTANTIALLY LINEAR GUIDE PATH IN SAID DIRECTION; DRAWING-DIE MEANSMOVABLY MOUNTED ON SAID SUPPORT MEANS FOR RECIPROCATION ALONG SAID GUIDEPATH; CLAMPING MEANS MOUNTED UPON SAID DRAWING-DIE MEANS ANDRECIPROCABLE RELATIVELY THERETO IN SAID DIRECTION FOR RELEASABLEENTRAINMENT OF SAID WIRE THROUGH SAID DRAWING-DIE MEANS;FLUID-RESPONSIVE MEANS ON SAID DRAWING-DIE MEANS CONNECTED WITH SAIDCLAMPING MEANS FOR RECIPROCABLY DISPLACING THE LATTER RELATIVELY TO SAIDDRAWING-DIE MEANS; AND DRIVE MEANS CONNECTABLE WITH SAID FEED MEANS FORADVANCING SAID WIRE IN SAID DIRECTION TOGETHER WITH SAID DRAWING-DIEMEANS AND SAID CLAMPING MEANS.